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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>

        let count = Array.from(new Set([1,2,3,4,5,6,23,4,4,5,56,6]))
        console.log(count);
        arr = [1,2,3,45,6,5,4,5,1,2]
        const set = new Set();
        arr.forEach(item => {
            set.add(item)
        });
        for(let item of set){
            console.log(item);
        }


        let map = new Map([['title','震惊'],['year','2020']]);
        map.forEach((item,value)=>{
            console.log(item); //震惊
            console.log(value); // title
        }
)
    </script>
    
</body>
</html>